98 MICRO-ORGANISMS AND FERMENTATION. 



large numbers on green malt, must certainly be given the first 

 place. It may even be considered doubtful whether the 

 greatest influence on the product must be attributed to the 

 mould-fungi (Penicillium, Aspergillus, etc.), when these are 

 met with in a state of vigorous development on malt, or 

 whether it is not far more probable that the numerous 

 organisms accompanying them play the most important 

 part. 



The author has often found a fine white parasitic growth on 

 the surface of pieces of pressed yeast, which rngst frequently 

 consists of a mould mycelium, belonging principally to forms 

 resembling O'idium, Chalara and Dematium. It is very 

 possible that when these plants form a thick layer on the 

 surface of the yeast-mass, they retain by respiration a portion 

 of the free oxygen which is necessary to enable the quiescent 

 yeast to remain alive. Even here, without exception, bacterial 

 growths occurred. 



The fact is, that, judging from observations made in 

 breweries and elsewhere, a growth of mould nearly always 

 serves to indicate that other organisms of a more injurious and 

 more active character are present in the growth. It is, there- 

 fore, of great importance that the walls of fermenting-rooms 

 should be smooth ; this is effected with the greatest certainty 

 by employing the enamel paint now so much in use. 



The following is a review of the most important moulds from 

 the point of view of the fermentation industries. 



1. BOTRYTIS CINEREA (Sclerotinia FucMiana) 



forms small greyish-yellow patches on moist, decaying vegetable 

 matter, and can also occur on wort. From the greyish-brown 

 mycelium the conidiophores are thrown up ; these are 

 perpendicular articulated filaments, generally arranged in tufts. 

 They grow to a height of 1 mm., after which the apical cell 

 throws out near its point, and almost at right angles, from two 

 to six small branches (C", Fig. 26). The lowest of these 

 branches are the longest ; these again develop downwards into 

 one or more short side branches. The topmost branches are 

 almost as wide as they are long. Thus a system of branches 



